1. Field of the Invention
The present invention relates to a portable cellular phone system which may be used as a stand alone unit or may be used in a vehicle. More particularly, the present invention relates to those portable cellular phone systems encased in a portable bag, which includes an internal power source, a transceiver/booster, and an antenna; or which may use the car battery for power and an external antenna for enhanced reception when used inside a vehicle.
2. Description of the Prior Art
Within the cellular phone industry, handheld cellular phones, hereafter referred to as portables, have a maximum output of six-tenths of a watt (0.6 watts). Mobile cellular car phones, hereafter referred to as mobile units, have maximum outputs of three (3) watts. There are also transportable cellular phones, hereafter referred to as transportables, which are carried in a case or a bag. These transportables have the same maximum output power rating as mobile phones. In fact, a transportable cellular phone is just a mobile unit installed in a bag or a hard case which can utilize an internal battery for power and antenna or can use vehicular power and external antenna.
Some manufactures have already designed three (3) watt booster systems to boost the output power of portables to the same full legal output power limit as a mobile phone. This type of system allows a user the convenience of utilizing a lightweight portable unit while on foot, while taking advantage of a vehicle's three (3) watt booster when used in a vehicle in which a three (3) watt booster system is installed.
U.S. Pat. No. 4,677,654 issued Jun. 30, 1987 to Steven R. Lagin discloses a portable cellular phone within a carrying case which may be used inside an automobile.
U.S. Pat. No. 4,962,523 issued Oct. 9, 1990 to Mituru Tanaka discloses a portable cellular phone unit with a built-in battery to supply power to the unit until a larger voltage is detected from an external power connection, in which case an automatic switch enables the unit to be powered through the use of the external power connection. The unit may thus be used as a stand-alone unit or within a vehicle.
U.S. Pat. No. 5,170,494 issued Dec. 8, 1992 to Lauri Levanto discloses a basic telephone unit which may be hooked up to a high powered amplification and transceiver or a low power amplification and transceiver system.
Japanese Patent No. 0117119 issued May 17, 1991 to Kono Mitsunori and European Patent Application No. 0452011 published Oct. 16, 1991 with Jarmo Heinonen listed as the sole inventor both disclose portable telephone sets which may be hooked up to a booster unit for amplifying the transmission signal.
None of the above inventions and patents, taken either singly or in combination, is seen to describe the instant invention as claimed.